Any downsides to switching to a 10W-30?

[wtd]

The engine that is having this problem is a 98 5.7L Vortec.

I want to clarify one point. I have not always had a cold startup tapping problem with this engine. It just started last year.

The noisy lifters I had when the truck was newer, only happened when I ran conventional oil. It pretty much went away when I switched to synthetic.

Wayne

 

[Patman]

I'm beginning to wonder if maybe you got some of the bad SuperSyn batch? The stuff like the one that Bob first tested, and the stuff that didn't have moly in it?

 

[VaderSS]

I never thought my engine was all that noisy, but since I've started running the 0W40, it has gotten even quieter.